Insulation boards, including foam insulation boards, are commonly used to enhance insulation of building structures. Relatively thin (about ¼ inch to about 3.0 inches), rectangular panels of foam board are commonly placed between the dry wall and building exteriors such as stone, brick, wood, stucco, etc. Such panels are referred to in the trade as “residential foam sheathing.” Insulation boards employed in such applications may include, but are not limited to, those utilizing polyisocyanurate foam and extruded polystyrene, polyolefin, and polyurethane foams and beads.
A problem encountered when using thin insulation boards is physical damage from bending, impact, or breaking. Such damage may occur by acts of vandalism, high velocity winds, rain, hail, construction practices, and the like. For example, in construction, it is common for ladders placed against vertical walls to bend or break the insulation boards. It is also common for construction personnel to kneel upon insulation boards during construction.
Foam insulation boards are subject to oxygen and water vapor transmission and structural damage, both of which, over time, contribute to deterioration of the insulation properties and reduce the structural integrity of the board. A technique to address the problems of physical damage and loss of insulation properties is to apply or adhere a facing material (called a “facer”) to at least one side of the board. Examples of such facing materials include plastic film, thin metal foil, paper or thin cellulose, non-woven polymeric fabrics, fiberglass scrims, and combinations of the foregoing.
Important properties of facers include serving as moisture vapor and oxygen transmission barriers, providing strength and structural integrity, ease of application, etc. Thin metal foils, such as aluminum, are commonly utilized in facers to provide moisture vapor and oxygen transmission barrier properties. However, such foils are often fragile and may contain pinholes, thereby reducing desired barrier properties.
Many laminates and/or facers for use in covering foam insulation boards and other products are described in the prior art. Such laminates are described in U.S. Pat. Nos. 6,355,701; 6,093,481; 6,044,604; 5,695,870; 5,565,252; 5,345,738; 5,044,705; 4,985,106; 4,764,420; 4,572,865; 4,509,307; 4,284,674; 4,254,173; and 3,903,346. However, none of the above-mentioned patents disclose laminates and/or facers having the sequence of layers and advantages derived thereby of this invention.
Above-mentioned U.S. Pat. No. 6,093,481 to Lynn et al. discloses a method for continuously manufacturing insulation boards by adhering facers over a foamed material. Illustrative of a facer that may be used is an outer layer of polyester film, an interior layer of fibrous material such as paper or glass, and a bottom layer of aluminum foil which is adhered to a foam core. Various layers including polymeric, metal foil, and fibrous materials are disclosed as possible components of the facers. Two trilaminate facers are described in FIG. 4 and at Column 5, lines 9-16 of the patent. Such trilaminates are further described as being preferred. As illustrated in the top portion of FIG. 4, an aluminum foil layer of the trilaminate is adhered to a foam core and a fibrous mid layer is adhered to the opposite side of the aluminum foil and also adhered to a tough polymeric outer layer. The patent discloses the use of another trilaminate on the opposite side of its foam core. Such trilaminate comprises the polymeric layer adhered to the foam, the same fibrous mid-layer, and an outer layer of aluminum foil.
The Lynn et al. patent also mentions the possible use of a coating to enhance gas barrier properties of its outer polymeric layer at Column 3, line 64-Column 4, line 8. Such coating is further described as a metallized polyester film coated with an UV and scratch-resistant oxidation barrier. With the properties of scratch resistance and UV resistance being mentioned, it is logical to believe that such coated layer would serve as an outer layer for the facer rather than disposed against the foam core of the insulation board or in a mid-portion of the facer.
Above-mentioned U.S. Pat. No. 3,903,346 to DeLeon et al. discloses a facer having aluminum foil adhered to a foam core and kraft paper adhered to said aluminum foil and a second aluminum foil adhered to said kraft paper to form an outer layer. The product described in this patent is believed to have been in commercial use for a considerable period of time and is one of the major facers used in the industry today.
The commercial product mentioned in the preceding paragraph includes an insulation board wherein polyisocyanurate foam is adhered to facers at each of its major opposed surfaces. The facers may be optionally adhered to the foam with use of a wash coat that interacts and bonds with the foam. One surface of aluminum foil is adhered to the wash coat or foam and the other surface to lightweight kraft paper (typically about 10 lbs. per 1,000 sq. ft.). The opposite surface of the paper is adhered to a second aluminum foil that serves as an outer layer for the insulation board.
It is desirable to provide a laminate and/or facer for uses that require improved oxygen and moisture vapor barrier properties, structural integrity, strength, and weatherability. Such improved properties are obtained due to the nature of the materials used in the laminate layers as well as by the sequence of such layers. In contrast to the prior art products mentioned above, the facer laminate of this invention provides improved protection to the foam core of an insulation board by utilizing a one-side metallized, preferably aluminum metallized, plastic layer adhered to one or both sides of the insulation foam board rather than aluminum foil. In the laminate of the invention, the bare or unmetallized side of the plastic layers or film is adhered to the foam core while the metallized side is adhered to fibrous material such as kraft paper. The fibrous material is then adhered to a protective plastic layer. Such sequence of materials of the invention provides superior protection of the foam core when contrasted with facers utilizing aluminum foil instead of metallized plastic proximate to the foam surface.